Coptodon Zillii (Redbelly Tilapia) Ecological Risk Screening Summary

Redbelly Tilapia (Coptodon zillii) Ecological Risk Screening Summary

U.S. Fish and Wildlife Service, May 2019 Revised, September 2019 Web Version, 11/18/2019

Photo: J. Hoover, Waterways Experiment Station, U.S. Army Corp of Engineers. Public domain. Available: https://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=485. (May 2019).

1 Native Range and Status in the United States Native Range From Froese and Pauly (2019a):

“Africa and Eurasia: South Morocco, Sahara, Niger-Benue system, rivers Senegal, Sassandra, Bandama, Boubo, Mé, Comoé, Bia, Ogun and Oshun, Volta system, Chad-Shari system [Teugels and Thys van den Audenaerde 1991], middle Congo River basin in the Ubangi, Uele [Thys van den Audenaerde 1964], Itimbiri, Aruwimi [Thys van den Audenaerde 1964; Decru 2015], Lindi-

Tshopo [Decru 2015] and Wagenia Falls [Moelants 2015] in Democratic Republic of the Congo, Lakes Albert [Thys van den Audenaerde 1964] and Turkana, Nile system and Jordan system [Teugels and Thys van den Audenaerde 1991].”

Froese and Pauly (2019a) list the following countries as part of the native range of Coptodon zillii: Algeria, Benin, Cameroon, Central African Republic, Chad, Democratic Republic of the Congo, Egypt, Ghana, Guinea, Guinea-Bissau, Israel, Ivory Coast, Jordan, Kenya, Lebanon, Liberia, Mali, Mauritania, Morocco, Niger, Nigeria, Senegal, Sierra Leone, Sudan, Togo, Tunisia, Uganda, and Western Sahara.

Status in the United States From NatureServe (2019):

“Introduced and established in ponds and other waters in Maricopa County, Arizona; irrigation canals in Coachella, Imperial, and Palo Verde valleys, California; and headwater springs of San Antonio River, Bexar County, Texas; common (Page and Burr 1991). Established also in the Carolinas, Hawaii, and possibly in Florida and Nevada (Robins et al. 1991).”

From Nico et al. (2019):

“Established or locally established in southern Arizona and California, Hawaii, North and South Carolina, and Texas; reported from several other states. Considered eradicated from all sites in Florida (Smith-Vaniz, personal communication) and Nevada (Courtenay et al. 1984, 1986). In California, Oreochromis mossambicus has largely replaced T. zillii in the Salton Sea (and possibly in coastal southern California) (Swift et al. 1993).”

“Populations introduced into Alabama normally did not survive the winter and required annual restocking (Smith-Vaniz 1968). However, their tolerance to cold temperatures in central California prompted officials to place the species on the prohibited list for portions of the state (Shapovalov et al. 1981).”

Very little information is available about current use of C. zillii in the United States. It does not appear to be common in aquaculture and is not available from major online aquarium and aquaponics retailers.

From Chapman (2018):

“In the United States, commercial culture of tilapia is concentrated in Arizona, California, and Florida. It is not clear, however, what species of tilapia are under cultivation. A collection of hybrid stocks currently constitute the bulk of the commercial production. The hybrids under cultivation are female mouth-brooders and believed to have originated from genetic crosses of predominantly blue tilapia (O. aureus) and ancillary O. niloticus, O. mossambicus, and O. hornorum species. Some evidence of genes from T. rendalli and S. melanotheron are also apparent.”

Most States regulate aquaculture species or facilities. The following information on State regulations is not exhaustive, and focuses on regulations that broadly prohibit importation, transport, or possession of C. zillii or the genus or family to which it belongs.

Florida Fish and Wildlife Conservation Commission (2019) lists “Tilapia [now Coptodon] zillii (Redbelly tilapia)” as a Prohibited Nonnative Species.

From Texas Parks and Wildlife (1999):

“The organisms listed here are legally classified as exotic, harmful, or potentially harmful. No person may possess or place them into water of this state except as authorized by the department [that is, Texas Parks and Wildlife].”

“Tilapia, Family Cichlidae All species of genera Tilapia, Oreochromis and Sarotherodon Examples: Tilapia [now Coptodon] zillii (Redbelly tilapia), […]”

“Note: Reclassification of a species does not remove the species from the prohibited list.”

From Aquatic Network (2019):

“No tilapia farming, or finfish farming at all is allowed in Alaska.”

“Currently, tilapia zilli, tilapia hornorum, and mossambica are the only species of tilapia allowed to be cultured in California and they are allowed only in the following counties: Riverside, Los Angeles, Orange, San Bernardino, San Diego, and Imperial. Please note that you must first obtain a Restricted Species Permit to possess, import, and transport tilapia [now Coptodon] zilli [sic].”

“According to the Illinois Department of Natural Resources: ‘It is unlawful for any person(s) to stock Tilapia species in Illinois waters. Tilapia are not on the Aquatic Life Approved Species List, but are allowed for aquaculture with an Aquaculture Permit and a Letter of Authorization to possess Tilapia. Aquatic Life Dealers may keep live Tilapia for sale at a market so long as all fish are dead upon sale.’”

“Tilapia are a restricted species in Nevada and can only be possessed alive in the state for purposes of commercial aquaculture, or certain other purposes. This requires a Commercial Possession of Live Wildlife License from the Department of Wildlife. Private possession of live tilapia for home or personal use is prohibited.”

“The Utah Division of Wildlife Resources (UDWR) has jurisdiction over the species of game fish one may possess in Utah. In other words, the UDWR must approve any species of game fish that a private operator may possess in Utah. Their ‘Collection, Importation and Possession of Zoological Animals’ regulation has classified Tilapia as a nuisance species and it does not allow importation or possession of the species in Utah.”

Means of Introductions in the United States From Nico et al. (2019):

“Introduced in most locations by state agencies, universities, or private companies for control of aquatic plants, to control mosquitoes and chironomid midges, as forage or food fish, and for aquaculture evaluation (Minckley 1973; Legner and Pelsue 1977; Lee et al. 1980 et seq.; Shapovalov et al. 1981; Grabowski et al. 1984; McGowan 1988; Courtenay and Robins 1989; Page and Burr 1991). For example, the species has been stocked into various North Carolina waters for aquatic plant control by Texas Gulf, Inc., and also by Carolina Power and Light Company (Courtenay et al. 1986; J. Crutchfield, personal communication). There have been both authorized as well as illegal releases. Introductions into Dade County, Florida, probably resulted from escapes from nearby fish farms or aquarium releases (Hogg 1976a, b). Redbelly tilapia and blue tilapia were inadvertently introduced into Hyco Reservoir in North Carolina in 1984 after a small number of fish escaped from a holding cage located in the heated discharge area during an on-site agricultural study (Crutchfield 1995).”

Remarks A previous version of this ERSS was finalized in 2014 under the name Tilapia zillii. Because the name T. zillii is still commonly used in literature, it was also used when researching in preparation of this report.

From CABI (2019):

“Tilapia zillii was first described by Gervais in 1848 and was given many synonyms throughout the nineteenth and twentieth century. Some sources recognize Coptodon zillii as the accepted name for the species following a molecular phylogenetic study by Dunz and Schliewen (2013).”

From GISD (2019):

“It seems to be a common mistake to omit one of the i's at the end of the word zillii, often incorrectly being spelled T. zilli.”

2 Biology and Ecology Taxonomic Hierarchy and Taxonomic Standing From Froese and Pauly (2019b):

“Biota > Animalia (Kingdom) > Chordata (Phylum) > Vertebrata (Subphylum) > Gnathostomata (Superclass) > Pisces (Superclass) > Actinopterygii (Class) > Perciformes (Order) > Labroidei (Suborder) > Cichlidae (Family) > Pseudocrenilabrinae (Subfamily) > Coptodon (Genus) > Coptodon zillii (Species)”

From Fricke et al. (2019):

“Current status: Valid as Coptodon zillii (Gervais 1848). Cichlidae: Pseudocrenilabrinae.”

Size, Weight, and Age Range From Froese and Pauly (2019a):

“Maturity: Lm 7.0, range 20 - ? cm Max length : 40.0 cm SL male/unsexed; [van Oijen 1995]; common length : 30.0 cm SL male/unsexed; [van Oijen 1995]; max. published weight: 300.00 g [Ita 1984]; max. reported age: 7 years [Noakes and Balon 1982]”

Environment From Froese and Pauly (2019a):

“Freshwater; brackish; benthopelagic; pH range: 6.0 - 9.0; dH range: 5 - 20; potamodromous [Riede 2004]; depth range 1 - 7 m [Eccles 1992].”

“Highly adaptable and tolerates varying water qualities [Lamboj 2004]; they are tolerant of a wide range of temperatures and salinities [Genner et al. 2018], even surviving marine conditions [Lamboj 2004]. Extended temperature range 6.5 - 42.5 °C, natural temperature range 10.5 - 36°C [Philippart and Ruwet 1982].”

From GISD (2019):

“While temperatures between 20 to 32 degrees Celsius are optimal for T. zillii, it can tolerate temperatures between 11 to 36 degrees Celsius, becoming lethargic and vulnerable to predators and disease below 16 degrees Celsius. Mostly occurring in fresh water, T. zillii are often found in brackish waters and has occasionally been reported to be found in marine waters; tolerating salinity levels of up to 29-45 ppt (Costa-Pierce, 2003; FishBase, 2008; GSMFC, 2005).”

From Nico et al. (2019):

“Redbelly tilapia is extremely tolerant of saline conditions, with survival and growth occurring in salinities up to 40‰ and reproduction occurring through 29‰ (Stickney 1986).”

Climate/Range From Froese and Pauly (2019a):

“Tropical; […] 35°N - 9°S, 17°W - 36°E”

Distribution Outside the United States Native From Froese and Pauly (2019a):

den Audenaerde 1964], Itimbiri, Aruwimi [Thys van den Audenaerde 1964; Decru 2015], Lindi- Tshopo [Decru 2015] and Wagenia Falls [Moelants 2015] in Democratic Republic of the Congo, Lakes Albert [Thys van den Audenaerde 1964] and Turkana, Nile system and Jordan system [Teugels and Thys van den Audenaerde 1991].”

Introduced From CABI (2019):

“Its non-native distribution includes Antigua and Barbuda, Eritrea, Ethiopia, Guam, Iran, Japan, Madagascar, Mauritius, Mexico, New Caledonia, Philippines, Saudi Arabia, Russia, Sri Lanka, Syria, Taiwan, Tanzania, Turkey, UK, […] Australia, Fiji, […] and Thailand (Froese and Pauly, 2014).”

From Gu et al. (2018):

“To date, five tilapia species (O. aureus, O. niloticus, Tilapia zillii, S. galilaeus, and a hybrid of O. mossambicus and O. niloticus) have been identified in the rivers of South China (Gu et al. 2016). Among these species, O. niloticus and T. zillii are most common, and they were both introduced to mainland China in 1978 and widely distributed in the study area (Gu et al. 2016, 2018).”

“Redbelly tilapia (Tilapia zillii) […] can tolerate colder waters and […] natural populations have developed in many rivers in South China (He et al. 2013).”

According to Froese and Pauly (2019a), C. zillii is established outside its native range in the following countries: Antigua, Ethiopia, Guam, Iraq, Israel, Japan, Jordan, Kenya, Madagascar, Mauritius, Mexico, New Caledonia, Saudi Arabia, Tanzania, Thailand, Turkey, and Uganda.

According to Froese and Pauly (2019a), C. zillii has been introduced but establishment has not been confirmed in the following countries: Australia, China, Eritrea, Fiji, Iran, Ivory Coast, Libya, Malaysia, Northern Marianas, Philippines, Russia, Singapore, South Africa, Sri Lanka, Syria, Taiwan, and the United Kingdom.

Means of Introduction Outside the United States From Khaefi et al. (2014):

“According to local fishermen, T. zillii appeared in this wetland [in Iran] in April or May 2012, and now it is available in daily catches. According to them, it was deliberately introduced to the Shadegan wetland to enhance fish production.”

From Ogutu-Ohwayo (1990):

“[…] Tilapia zillii (Gervais), were introduced into lakes Victoria and Kyoga [East Africa] during the 1950s and early 1960s. […] T. zillii was introduced to feed on macrophytes which were not being utilized by other commercially important fishes.”

Short Description From Froese and Pauly (2019a):

“Dorsal spines (total): 13 - 16; Dorsal soft rays (total): 10-14; Anal spines: 3; Anal soft rays: 8 - 10. Diagnosis: A large, deep-bodied species with a narrow head and small strong jaws; generally has a bright red belly and prominent vertical barring [Genner et al. 2018]. Upper profile of head not convex; lower pharyngeal bone about as long as broad, and with anterior lamella shorter than toothed area; median pharyngeal teeth not broadened; dorsal fin with 14-16 spines and 10-14 soft rays; 8-11 lower gillrakers; dark longitudinal band appears on flanks when agitated; no bifurcated dark vertical bars on flanks; dorsal and caudal fins not or feebly blotched [Teugels and Thys van den Audenaerde 2003]. Body brownish-olivaceous with an iridescent blue sheen; lips bright green [van Oijen 1995; Teugels and Thys van den Audenaerde 2003]. Chest pinkish [van Oijen 1995]. Dorsal, caudal and anal fins brownish-olivaceous with yellow spots, dorsal and anal fins outlined by narrow orange band; "tilapian" spot large, extending from last spine to 4th soft ray and always bordered by yellow band [van Oijen 1995; Teugels and Thys van den Audenaerde 2003]. Specimens of 2-14 cm standard length with completely yellowish or greyish caudal fin without dots, but tend to develop a greyish caudal fin with dots of increasing size during development; above 14 cm standard length, this species has greyish caudal fins with dots on entire caudal fin [Nobah et al. 2006]. The sexes look very similar, although in a mated pair the male is usually larger [Genner et al. 2018]. Difficult to distinguish reliably from Coptodon rendalli, but C. zillii can have a less-steep head profile and more prominent vertical bars; in East Africa, the tailfin of C. rendalli is often divided into a brown/grey upper part and red/yellowish lower part, whereas the tail of C. zillii is more uniform throughout [Genner et al. 2018].”

Biology From Nico et al. (2019):

“Redbelly tilapia is primarily herbivorous, with aquatic macrophytes, algae, and diatoms generally comprising >80% of its diet and the remainder including aquatic insects and crustaceans and fish eggs. Proportion of diet from animal sources is generally size-related, with larger fish consuming more animal-based food items (Khallaf and Alne-na-ei 1987). […] This species is a substrate spawner, with fishes forming monogamous pairs and exhibiting biparental guarding behavior. Nests are primarily small, saucer-shaped depressions in the substrate, but show some variation in morphology due to environmental conditions (Bruton and Gophen 1992). Breeding season is dependent on climate, with warm, temperature-stable equatorial populations breeding year-round, and those in areas with more defined seasons breeding during summer months (Siddiqui 1979; Bruton and Gophen 1992).”

Human Uses From CABI (2019):

“Redbelly tilapia is an economically important food fish and important to aquaculture and commercial aquarium trade in its native range (Mehanna, 2004).”

“It provides up to 70% of Egypt’s fish production and is a hardy species, easy to grow and popular with consumers (white-fleshed and mild-flavoured) (Canonico et al., 2005).”

“It is also an important fish species for recreational fishery (ISSG, 2014). In addition to its value for commercial fishermen, recreational fishing and tourism may create a demand not only for food, accommodation and transportation but also for related recreational activities such as camping, boating, etc. All of these activities may provide economic incomes.”

“Redbelly tilapia is used for controlling species of aquatic plants. It was determined that Chara sp. and Najasmarina [sic] could be controlled by redbelly tilapia in small lakes and ponds (Saeed, 1986). It has also been used to control noxious aquatic insects, mosquitos and chrinomid [sic] midges (Molnar [et al.], 2008).”

Diseases No OIE-reportable diseases (OIE 2019) have been documented for this species.

Poelen et al. (2014) lists the following as parasites of Coptodon zillii: Acanthogyrus tilapiae, Euclinostomum heterostomum, Posthodiplostomum sp., Amirthalingamia macracantha, Cichildogyrus tilapiae, Polyacanthorhynchus kenyensis, Cichlidogyrus amphoratus, Cichlidogyrus digitatus, Cichlidogyrus yanni, Argulus sp., Porrocaecum sp., and Strigeidae sp. (Strona et al. 2013, Benesh et al. 2017, Smithsonian Institution no date).

From CABI (2019):

“Redbelly tilapia may be infected with a wide range of diseases and parasites, including Diplozoon paradoxum and Tetraonchus species (Yildirim et al., 2010).”

Threat to Humans From Froese and Pauly (2019a):

“Potential pest”

3 Impacts of Introductions From Nico et al. (2019):

“Juvenile T. zillii were implicated in population declines of desert pupfish Cyprinodon macularius inhabiting shallow irrigation canals near the Salton Sea, California (Lee et al. 1980 et seq.; Schoenherr 1985). In Florida, this species was found to be highly aggressive; it is

considered a serious threat to native aquatic plants and to fish that rely on plants for cover, foraging, or spawning sites (Courtenay et al. 1974).”

From Crutchfield et al. (1992):

“Redbelly tilapia (Tilapia zilli Gervais) rapidly established a reproducing population in a North Carolina power plant cooling reservoir after inadvertent introduction in 1984. It eliminated the submersed macrophyte community, including a 57-ha infestation of Egeria densa (Planch.) [nonnative] by late 1985.”

From Andreu-Soler and Ruiz-Campos (2013):

“We assessed the effects of the abundance and biomass of four exotic fishes (common carp, Cyprinus carpio; guppy, Poecilia reticulata; green swordtail, Xiphophorus hellerii; and redbelly tilapia, Tilapia cf. zillii) on the residual somatic condition (Kr) of endangered Baja California killifish (Fundulus lima) in two oasis systems of Baja California Sur, Mexico. We used multiple regressions to analyze relationships between Kr of the killifish and 21 ecological variables. Biomass of redbelly tilapia and common carp were variables that better explained variation in Kr among populations of killifish. In both drainages, redbelly tilapia was the dominant fish, which relegated smaller habitat units to the other coexisting species of fishes, increasing competition among them and decreasing Kr and abundance of the endemic killifish.”

Most States regulate aquaculture species or facilities. The following States (not an exhaustive list) have regulations that broadly prohibit importation, transport, or possession of C. zillii: Alaska, California, Florida, Illinois, Nevada, Texas, and Utah (Texas Parks and Wildlife 1999; Aquatic Network 2019; Florida Fish and Wildlife Conservation Commission 2019).

4 Global Distribution

Figure 1. Known global distribution of Coptodon zillii. Map from GBIF Secretariat (2019). Points in Angola, Australia, Botswana, Eritrea, Guyana, Mozambique, Réunion, the Seychelles, South Africa, Syria, the United Kingdom, Zambia were excluded from climate matching because the establishment status of C. zillii has not been confirmed in these countries. Points in the contiguous United States that were inconsistent with the established U.S. range of C. zillii as reported by Nico et al. (2019; Figure 2) were also excluded from climate matching analysis. No occurrence data were available for parts of the species established range in Antigua, Iraq, New Caledonia, Saudi Arabia, and Turkey.

5 Distribution Within the United States

Figure 2. Known distribution of Coptodon zillii in the United States. Map from Nico et al. (2019). Yellow diamonds represent established occurrences; orange diamonds represent all other status designations (failed, collected, extirpated, unknown, or stocked). Point in Idaho was excluded from climate matching analysis because it is located in a geothermal water body.

6 Climate Matching Summary of Climate Matching Analysis The Climate 6 score (Sanders et al. 2018; 16 climate variables; Euclidean distance) for the contiguous United States was 0.347, indicating a high overall climate match. (A Climate 6 score of 0.103 or greater is classified as high.) The climate match was high in peninsular Florida, the Mid-Atlantic Region, much of Texas, the Southwest, California, and scattered areas in the Pacific Northwest. Most of the rest of the contiguous United States had a medium climate match. There were areas of low climate match in the Pacific Northwest, New England, interior Southeast, and the north-central United States from the western Great Lakes to the eastern Rocky Mountains. Individual States had medium or high climate scores except for the following States that had low climate scores: Alabama, Colorado, Iowa, Maine, Michigan, Minnesota, Mississippi, North Dakota, Nebraska, New Hampshire, Rhode Island, South Dakota, Vermont, Wisconsin, and Wyoming.

Figure 3. RAMP (Sanders et al. 2018) source map showing weather stations selected as source locations (red; southern United States and Hawaii; Mexico; West, Central, and East Africa including Madagascar; scattered locations in North Africa; Israel; Lebanon; Jordan; Thailand; China; Japan) and non-source locations (gray) for Coptodon zillii climate matching. Source locations from GBIF Secretariat (2019) and Nico et al. (2019).

Figure 4. Map of RAMP (Sanders et al. 2018) climate matches for Coptodon zillii in the contiguous United States based on source locations reported by GBIF Secretariat (2019) and Nico et al. (2019). 0 = Lowest match, 10 = Highest match.

The “High”, “Medium”, and “Low” climate match categories are based on the following table:

Climate 6: Proportion of Climate Match (Sum of Climate Scores 6-10) / (Sum of total Climate Scores) Category 0.000≤X≤0.005 Low 0.005

7 Certainty of Assessment There is adequate information available about the biology and distribution of Coptodon zillii. Its invasion history, both in the United States and globally, has been well-documented. Negative impacts of this species’ introduction have been reported from multiple geographic locations in multiple studies in the scientific literature. Certainty of this assessment is high.

8 Risk Assessment Summary of Risk to the Contiguous United States Coptodon zillii, the Redbelly Tilapia, is a fish species native to Africa and the Middle East. It is adaptable to a wide range of environments and has been introduced in many countries for aquaculture, recreational fishing, forage, and control of aquatic macrophyte or insects. C. zillii is also used for commercial fishing and in the aquarium trade. Many of these introductions have resulted in population establishment. C. zillii is not heavily in use in the United States currently, but it has become established in the southern United States through a history of deliberate release and accidental escape from captivity. Several States regulate importation, transport, or possession of C. zillii. Declines of native fish species, such as the endangered Baja California Killifish and the desert pupfish Cyprinodon macularius, have been attributed to C. zillii. C. zillii also eliminated the aquatic macrophyte community of the Hyco Reservoir in North Carolina. History of invasiveness is high. This species has a high climate match with the contiguous United States, especially in the southern United States where it is already established. Certainty of this assessment is high because negative impacts of this species’ introduction have been clearly documented in the scientific literature in multiple locations. The overall risk assessment category is high.

Assessment Elements  History of Invasiveness (Sec. 3): High  Climate Match (Sec. 6): High  Certainty of Assessment (Sec. 7): High  Overall Risk Assessment Category: High

9 References Note: The following references were accessed for this ERSS. References cited within quoted text but not accessed are included below in Section 10.

Andreu-Soler, A., and G. Ruiz-Campos. 2013. Effects of exotic fishes on the somatic condition of the endangered Killifish Fundulus lima (Teleostei: Fundulidae) in oases of Baja California Sur, Mexico. The Southwestern Naturalist 58(2):192-201.

Aquatic Network. 2019. United States aquaculture by regions. Available: https://www.aquanet.com/us-regulations. (September 2019).

CABI. 2019. Tilapia zillii (redbelly tilapia) [original text by A. S. Tarkan]. In Invasive Species Compendium. CAB International, Wallingford, U.K. Available: https://www.cabi.org/ISC/datasheet/61147. (May 2019).

Chapman, F. A. 2018. Culture of hybrid tilapia: a reference profile. CIR1051. University of Florida/Institute of Food and Agricultural Sciences, Gainesville, Florida.

Crutchfield, J. U., Jr., D. H. Schiller, D. D. Herlong, and M. A. Mallin. 1992. Establishment and impact of redbelly tilapia in a vegetated cooling reservoir. Journal of Aquatic Plant Management 30:28-35.

Florida Fish and Wildlife Conservation Commission. 2019. Prohibited nonnative species list. Florida Fish and Wildlife Conservation Commission, Tallahassee. Available: https://myfwc.com/wildlifehabitats/nonnatives/prohibited-species-list/. (May 2019).

Fricke, R., W. N. Eschmeyer, and R. van der Laan, editors. 2019. Catalog of fishes: genera, species, references. Available: http://researcharchive.calacademy.org/research/ichthyology/catalog/fishcatmain.asp. (May 2019).

Froese, R., and D. Pauly, editors. 2019a. Coptodon zillii Gervais, 1848. FishBase. Available: https://www.fishbase.de/summary/Coptodon-zillii.html. (May 2019).

Froese, R., and D. Pauly, editors. 2019b. Coptodon zillii (Gervais, 1848). FishBase. In World Register of Marine Species. Available: http://www.marinespecies.org/aphia.php?p=taxdetails&id=317356. (September 2019).

GBIF Secretariat. 2019. GBIF backbone taxonomy: Coptodon zillii (Gervais, 1848). Global Biodiversity Information Facility, Copenhagen. Available: https://www.gbif.org/species/2370703. (September 2019).

GISD (Global Invasive Species Database). 2019. Species profile: Tilapia zillii. Invasive Species Specialist Group, Gland, Switzerland. Available: http://www.iucngisd.org/gisd/speciesname/Tilapia+zillii. (May 2019).

Gu, D. E., F. D. Yu, M. Xu, H. Wei, X. D. Mu, D. Luo, Y. X. Yang, Z. Pan, and Y. C. Hu. 2018. Temperature effects on the distribution of two invasive tilapia species (Tilapia zillii and Oreochromis niloticus) in the rivers of South China. Journal of Freshwater Ecology 33(1):511-524.

Khaefi, R., H. R. Esmaeili, H. Zareian, and S. Babaei. 2014. The first record of the redbelly tilapia, Tilapia zillii (Gervais, 1848), in freshwaters of Iran. Turkish Journal of Zoology 38:96-98.

NatureServe. 2019. NatureServe Explorer: an online encyclopedia of life, version 7.1. NatureServe, Arlington, Virginia. Available: http://explorer.natureserve.org. (May 2019).

Nico, L., M. Neilson, and B. Loftus. 2019. Tilapia zillii (Gervais, 1848). U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, Florida. Available: https://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=485. (May 2019).

Ogutu-Ohwayo, R. 1990. The decline of the native fishes of lakes Victoria and Kyoga (East Africa) and the impact of introduced species, especially the Nile perch, Lates niloticus,

and the Nile tilapia, Oreochromis niloticus. Environmental Biology of Fishes 27(2):81- 96.

OIE (World Organisation for Animal Health). 2019. OIE-listed diseases, infections and infestations in force in 2019. World Organisation for Animal Health, Paris. Available: https://www.oie.int/animal-health-in-the-world/oie-listed-diseases-2019/. (September 2019).

Poelen, J. H., J. D. Simons, and C. J. Mungall. 2014. Global Biotic Interactions: an open infrastructure to share and analyze species-interaction datasets. Ecological Informatics 24:148-159.

Sanders, S., C. Castiglione, and M. H. Hoff. 2018. Risk Assessment Mapping Program: RAMP, version 3.1. U.S. Fish and Wildlife Service.

Texas Parks and Wildlife. 1999. Exotic fish, shellfish, and invasive aquatic plants. Texas Parks and Wildlife Department, Austin. Available: https://tpwd.texas.gov/huntwild/wild/species/exotic/prohibited_aquatic.phtml. (May 2019).

10 References Quoted But Not Accessed Note: The following references are cited within quoted text within this ERSS, but were not accessed for its preparation. They are included here to provide the reader with more information.

Benesh, D. P., K. D. Lafferty, and A. Kuris. 2017. A life cycle database for parasitic acanthocephalans, cestodes, and nematodes. Ecology 98(3):882.

Bruton, M. N., and M. Gophen. 1992. The effect of environmental factors on the nesting and courtship behaviour of Tilapia zillii in Lake Kinneret (Israel). Hydrobiologia 239:171- 178.

Canonico, G. C., A. Arthington, J. K. McCrary, and M. L. Thieme. 2005. The effects of introduced tilapias on native biodiversity. Aquatic Conservation: Marine and Freshwater Ecosystems 15:463-483.

Costa-Pierce, B. A. 2003. Rapid evolution of an established feral tilapia (Oreochromis spp.): the need to incorporate invasion science into regulatory structures. Biological Invasions 5:71- 84.

Courtenay, W. R., Jr., D. A. Hensley, J. N. Taylor, and J. A. McCann. 1984. Distribution of exotic fishes in the continental United States. Pages 41-77 in W. R. Courtenay, Jr., and J. R. Stauffer, Jr., editors. Distribution, biology and management of exotic fishes. John Hopkins University Press Baltimore, Maryland.

Courtenay, W. R., Jr., D. A. Hensley, J. N. Taylor, and J. A. McCann. 1986. Distribution of exotic fishes in North America. Pages 675-698 in C. H. Hocutt, and E. O. Wiley, editors. The zoogeography of North American freshwater fishes. John Wiley and Sons, New York.

Courtenay, W. R., Jr., and C. R. Robins. 1989. Fish introductions: good management, mismanagement, or no management? CRC Critical Reviews in Aquatic Sciences 1(1):159-172.

Courtenay, W. R., Jr., H. F. Sahlman, W. W. Miley II, and D. J. Herrema. 1974. Exotic fishes in fresh and brackish waters of Florida. Biological Conservation 6(4):292-302.

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